I've tried sending a number of test emails to at least three email addresses I have waited for 2 hours before receive something.
Do you know why this happens?
It depends on whether Marketo sent the email immediately and it took 3 hours to be delivered or whether Marketo took 3 hours to send it. This can be seen from the lead's activity log.
In the first case, it might be linked to your own email servers being overloaded, or any issue between Marketo sending servers and your emailing servers.
In the second case, this because your Marketo instance is overloaded and has a hard time catching up with the workload, and therefore having your smarrt campaign running late. It also means that the way you smart campaign sending the email is not set up to maximize priority. Set it so that the "send email" flow step is the first one, and it's priority will be higher. But you would still have to understand what's jamming your instance. Start with the campaign queue.
Thank you for your answer, but I don't use smart campaign to send test emails.
Well, it would take a detailed examination of the email routing to known exactly what's wrong
Another possibility : make sure that Marketo email servers are correcly white listed in your own emailing system.
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